Intermittent Keto: Healthy Or Harmful?

The ketogenic (keto) diet is a popular, restrictive, high-fat, low-carb eating plan. It involves reducing your daily carbohydrate intake to a maximum of 20 to 50 grams, forcing your body to rely on burning fat for energy instead of glucose. This metabolic state is called ketosis. Intermittent fasting (IF) is another popular health trend, which involves eating within a specified time window and avoiding food for the remaining hours. Some people combine keto and IF to accelerate weight loss, but is this safe?

Intermittent keto and intermittent fasting can be a powerful combination for weight loss

The ketogenic (keto) diet and intermittent fasting are two of the most popular health trends for weight loss and controlling certain health conditions. The keto diet is a high-fat, very low-carb way of eating, while intermittent fasting involves cycling between periods of calorie restriction (or fasting) and normal food consumption.

Combining these two approaches can be a powerful tool for weight loss and offers several potential benefits:

Reach Ketosis Faster

Intermittent fasting can help your body reach ketosis quicker than with the keto diet alone. During fasting, your body's fuel source shifts from carbs to fats, which is the basis of the keto diet. Insulin levels and glycogen stores decrease, leading your body to naturally start burning fat for fuel.

Increased Fat Loss

Combining intermittent fasting with the keto diet may help burn more fat. Intermittent fasting boosts metabolism by promoting thermogenesis, or heat production, which can target stubborn fat stores. Studies have shown that intermittent fasting can lead to significant fat loss, even when compared to very low-calorie diets.

Preserve Muscle Mass

Intermittent fasting may help preserve muscle mass during weight loss, which is important for those looking to improve athletic performance. A review of human studies found that intermittent fasting paired with resistance training preserved lean body mass while reducing body fat.

Reduce Hunger

Intermittent fasting can reduce hunger and promote feelings of fullness, which can aid in weight loss. This can be especially helpful for those on the keto diet, as it may be challenging to stick to a strict low-carb diet.

Improve Metabolic Flexibility

Intermittent fasting and keto can make your body more metabolically flexible, meaning it can easily switch between burning sugar (glucose) and ketones (fat) depending on the available energy source. This is linked to better weight management and improved exercise performance.

Break Through Plateaus

For those who have lost weight on keto but hit a plateau, adding intermittent fasting can be a game-changer. Intermittent fasting reduces your overall calorie intake and can help you overcome a stall in weight loss.

While combining intermittent keto and intermittent fasting can be a powerful weight-loss strategy, it may not be suitable for everyone. It is important to consult with a healthcare professional before starting any new diet, especially if you have a medical condition, are pregnant or breastfeeding, or have a history of disordered eating. Additionally, this combination may be challenging to stick to due to the restrictive nature of both diets.

Intermittent keto may be unsafe for pregnant or breastfeeding women

The keto diet restricts carbohydrates and is high in saturated fat, which can make it difficult for pregnant women to get the nutrients they need. Folic acid, for example, is found in carbohydrate-rich foods and is key to the baby's brain and spine development. Doctors recommend limiting saturated fats to control pregnancy weight gain and avoid complications like high blood pressure.

In addition, the keto diet may cause nutrient deficiencies in pregnant women. They need vitamins and minerals such as vitamin D, vitamin E, vitamin B-12, and folic acid, which are found in brightly coloured fruits and vegetables. The keto diet restricts these foods, which can lead to problems in the baby's growth and development.

Some studies on animals have shown that a keto diet during pregnancy may cause changes to embryo development and increase the risk of anxiety and depression in the offspring. However, one study found that exposure to a ketogenic diet increased sociability in the offspring. More research is needed to determine the safety of the keto diet during pregnancy, especially in humans.

Overall, it is best for pregnant and breastfeeding women to avoid intermittent keto as it may negatively affect fetal development and milk supply. Instead, doctors recommend a balanced diet of fruits, vegetables, grains, lean protein, and dairy products to ensure the nutritional needs of both mother and baby are met.

Intermittent keto may not be suitable for people with type 2 diabetes

The keto diet restricts carbohydrates, forcing the body to break down fats for energy and resulting in a process called ketosis. This shift in energy sources can lead to some adverse effects, including short-term side effects such as "keto flu", constipation, and a loss of energy. More importantly, it can also cause a dangerous condition called ketoacidosis, where the blood becomes too acidic due to high levels of ketones. While ketoacidosis is more common in people with type 1 diabetes, it can also occur in those with type 2 diabetes, especially if combined with prolonged fasting or certain medications.

Additionally, the keto diet may not be suitable for people with type 2 diabetes as it can lead to an increased risk of nutrient deficiencies, constipation, and loose skin due to rapid weight loss. It is also important to note that the keto diet should not be approached as a quick fix, as yo-yo dieting can be dangerous for people with diabetes. Instead, it is recommended to work with a healthcare professional to develop an individualized diet plan that considers personal needs, preferences, and health goals.

Intermittent keto may lead to micronutrient losses or electrolyte deficiencies

The keto diet restricts carbohydrates, which are found in whole grains, fruits, and vegetables. These foods are typically rich in micronutrients such as vitamins, minerals, and fibre. By cutting out these food groups, the body may not be getting enough of the essential micronutrients it needs.

In addition, the keto diet also recommends limiting protein intake as too much protein can interfere with ketosis. This can further contribute to micronutrient deficiencies, as protein-rich foods such as lean meats, fish, and beans are also good sources of micronutrients.

Furthermore, the keto diet encourages a high intake of saturated fats, which can lead to an increased risk of heart disease. Saturated fats are typically found in animal products such as meat, dairy, and eggs. While these foods do contain some micronutrients, such as vitamins A, D, E, and K, they are not sufficient to meet the body's daily requirements.

To avoid micronutrient losses or electrolyte deficiencies while on the keto diet, it is important to carefully plan meals and ensure a varied diet that includes nutrient-dense foods. It may also be beneficial to work with a registered dietitian to ensure that micronutrient needs are being met.

Intermittent keto may not be sustainable long-term

The keto diet is a high-fat, very-low-carb, and moderate-protein eating plan. It involves cutting out most carbs, even healthy foods such as whole grains and fruits. The diet is so restrictive that it can be a challenge to get all the nutrients your body needs.

Intermittent fasting is an eating pattern that involves cycling between periods of fasting and normal eating. It can be done in several ways, such as the 5:2 method, the 16/8 method, or alternate-day fasting. When combined with the keto diet, it can lead to a drastic reduction in calories and micronutrients.

While the combination of intermittent fasting and keto may lead to increased weight loss, it is not necessarily safe or sustainable long-term. It can be challenging to stick to such a restrictive diet and may not be suitable for everyone.

Additionally, there is a lack of rigorous research on the combined approach, and it has not been proven to be more effective for weight loss than either method alone. Some experts even warn that the combination could be dangerous for certain individuals, such as those with diabetes or a history of eating disorders.

Therefore, while intermittent keto may lead to faster weight loss, it may not be a sustainable long-term solution for most people due to its restrictive nature and lack of supporting research.

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